diff mbox series

[next] fs/9p: fix uaf in in v9fs_stat2inode_dotl

Message ID 20240202121531.2550018-1-lizhi.xu@windriver.com
State New
Headers
Series [next] fs/9p: fix uaf in in v9fs_stat2inode_dotl |

Commit Message

Lizhi Xu Feb. 2, 2024, 12:15 p.m. UTC 
  The incorrect logical order of accessing the st object code in v9fs_fid_iget_dotl
is causing this uaf.

Fixes: 724a08450f74 ("fs/9p: simplify iget to remove unnecessary paths")
Reported-and-tested-by: syzbot+7a3d75905ea1a830dbe5@syzkaller.appspotmail.com
Signed-off-by: Lizhi Xu <lizhi.xu@windriver.com>
---
 fs/9p/vfs_inode_dotl.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Breno Leitao Feb. 28, 2024, 10:33 a.m. UTC | #1 
On Fri, Feb 02, 2024 at 08:15:31PM +0800, Lizhi Xu wrote:
> The incorrect logical order of accessing the st object code in v9fs_fid_iget_dotl
> is causing this uaf.
> 
> Fixes: 724a08450f74 ("fs/9p: simplify iget to remove unnecessary paths")
> Reported-and-tested-by: syzbot+7a3d75905ea1a830dbe5@syzkaller.appspotmail.com
> Signed-off-by: Lizhi Xu <lizhi.xu@windriver.com>

Tested-by: Breno Leitao <leitao@debian.org>
Dominique Martinet March 4, 2024, 1:02 p.m. UTC | #2 
Lizhi Xu wrote on Fri, Feb 02, 2024 at 08:15:31PM +0800:
> The incorrect logical order of accessing the st object code in v9fs_fid_iget_dotl
> is causing this uaf.

Thanks for the fix!

Eric, this is also for your tree.

> 
> Fixes: 724a08450f74 ("fs/9p: simplify iget to remove unnecessary paths")

(careful if you rebase your tree as this commit isn't merged yet)

> Reported-and-tested-by: syzbot+7a3d75905ea1a830dbe5@syzkaller.appspotmail.com
> Signed-off-by: Lizhi Xu <lizhi.xu@windriver.com>

Reviewed-by: Dominique Martinet <asmadeus@codewreck.org>
diff mbox series

Patch

diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c
index ef9db3e03506..2b313fe7003e 100644
--- a/fs/9p/vfs_inode_dotl.c
+++ b/fs/9p/vfs_inode_dotl.c
@@ -78,11 +78,11 @@  struct inode *v9fs_fid_iget_dotl(struct super_block *sb, struct p9_fid *fid)
 
 	retval = v9fs_init_inode(v9ses, inode, &fid->qid,
 				 st->st_mode, new_decode_dev(st->st_rdev));
+	v9fs_stat2inode_dotl(st, inode, 0);
 	kfree(st);
 	if (retval)
 		goto error;
 
-	v9fs_stat2inode_dotl(st, inode, 0);
 	v9fs_set_netfs_context(inode);
 	v9fs_cache_inode_get_cookie(inode);
 	retval = v9fs_get_acl(inode, fid);